The results of a well-testing study of Kewaunee County water are likely to be discussed when the county Land and Water Conservation Committee meets at 9 a.m. Tuesday at the Land and Water Conservation Department in the Fairgrounds building, 625 Third St., Luxemburg.
USDA microbiologist Mark Borchardt and his team presented the results of a two-year study of contamination in private wells. The study drew links between polluted wells, spring and fall manure spreading on fields with shallow soil, and failing septic systems.
“It’s good to have this information,” committee chairman John Pagel said after the presentation. “The data will help us determine what has to be changed; we’re already doing some of those changes.”
Supervisor Lee Luft, another committee member and former chairman of the now-dissolved county Groundwater Task Force, agreed that it’s helpful to have data that confirms the causes of well contamination.
“Now let’s be careful of how we spread, let’s not add any more sources to the waste stream, and let’s be aware of where you’re farming,” Luft said after the June 7 meeting.
The study revealed that about 208 of the 621 tested wells showed contamination from bacteria or high nitrate levels, and a review of the pathogens in the contaminated wells showed levels well above the state average. There was evidence of both bovine and human waste in the affected wells.
The levels were especially high in areas with 5 feet or less of soil over bedrock, and to only a slightly lesser extent when the depth to bedrock was 5-20 feet.
Tuesday’s meeting is also the committee’s first chance to discuss draft ordinances regulation waste irrigation and waste haulers in Kewaunee County.
The ordinances are the county’s latest effort to deal with the practice of spreading large amounts of liquid manure onto fields in the winter and fall, which is considered a major source of groundwater contamination issues in the county. An ordinance is already in place banning winter and early spring spreading on shallow soil over fragile karst bedrock, where contamination can quickly flow into water via fractures in the bedrock.